Can you guys help me choose a class for pvp ?

Hey,

My Pve main is a lock and it has been a long time since i pvped on any character in wow because most of the time i was pveing. I want to start doing arenas again and I have some good Xp in PVP i have reach 2k+ in arena and RBGS before.

I was thinking of choosing between a lock, enhancement shaman or a WW.
I want a class that is able to play competitively with a large number of comps and a class that has a good balance between survivability and Damage.

PS: I am willing to try any class, i have good pvp experience with most in the past

Don't go enhance if you want to be able to play a large number of comps... or is competitive..
I've played WoW for 8 years now and (except i think season 9 possible) warlocks are consistently pretty powerful and useful, plays alot of comps
WW - I rerolled WW for MOP and they're pretty much unstoppable, but i'd say from my experience... (maybe i just suck at arena idk) that WW is more tuned for battlegrounds, than it is for arena

If you are already playing a warlock, go with it. You have many strong (rank 1 strong) comps to play in! And you have many "just for fun" comps that will work up to a very good rating anyway. Warlocks are currently great - go with it